The present invention relates to an improved method of and apparatus for the protection of well components from damage due to being exposed to excessive pressure resulting from the downhole environment in which they are to operate.
U.S. Pat. No. 4,662,663 discloses the use of a volume compensating material on the interior of a first tubular member which is to have a second tubular member pressure formed into a grooved surface on the interior of the first tubular member at an underwater location. The volume compensating material is utilized to exclude water from the grooves so that it will not create a hydraulic lock preventing proper deformation of the second tubular member into sealing and gripping engagement within the grooves on the interior of the first tubular member. One material suggested for this volume compensating material is a plurality of microspheres held in an epoxy matrix.
This type of material is designed to function to cause the microspheres to rupture upon the application of pressure and allow the entry therein of any trapped liquid and to crush at excessive forming pressures to thereby allow the completion of the pressure forming. Another reference making similar suggestions is U.S. Pat. No. 4,593,448.
A recently issued U.S. Pat. No. 4,869,535 discloses the use of such volume compensating material in a downhole environment, particularly in an annular chamber into which an annular piston moves responsive to pressure. In this patent the volume compensating material functions to exclude fluids which might prevent the desired movement of the piston and allows such movement by the crushing of the material responsive to the pressure force exerted thereon by the pressured piston.